In recent years considerable attention has been focused on the amount of triglyceride fat in the diet from the standpoint of health concerns about obesity and hypercholesterolemia. Numerous patents have been directed to providing materials which have the physical and gustatory characteristics of triglyceride fats, but which are absorbed to a low extent or not at all by the body. These materials are referred to variously as noncaloric fats, pseudofats, nondigestible fats and fat substitutes. Patents pertaining to such materials include U.S. Pat. No. 4,582,927, Fulcher, issued Apr. 15, 1986, (fatty esters of malonic acid); U.S. Pat. No. 4,582,715, Volpenhein, issued Apr. 15, 1986, (alpha acetylated triglycerides); and U.S. Pat. No. 3,579,548, Whyte, issued May 18, 1971, (triglycerides of alpha-branched chain carboxylic acids)
One particular type of compound which has achieved considerable attention as a nondigestible fat is sucrose polyester (i.e., sucrose in which at least four of the eight hydroxyl groups are esterified with a fatty acid). U.S. Pat. No. 3,600,186, Mattson, issued Aug. 17, 1971; U.S. Pat. No. 4,368,213, Hollenbach et al. issued Jan. 11, 1983; and U.S. Pat. No. 4,461,782, Robbins et al. issued Jul. 24, 1984 describe the use of this material as a nondigestible fat in a variety of food compositions.
A problem associated with use of liquid nondigestible oils, i.e., those having a melting point below body temperature (about 37.degree. C.), is an undesired passive oil loss effect, (hereinafter "oil loss") which is manifested in leakage of the liquid nondigested fat through the gastrointestinal tract's anal sphincter. Regular ingestion of moderate to high levels of completely liquid forms of these polyol polyesters can produce this passive oil loss. U.S. Pat. No. 4,005,195, Jandacek, issued Jan. 25, 1977, discloses the combining of higher melting fatty materials such as solid triglycerides and solid sucrose polyesters with the liquid sucrose polyesters in order to control oil loss.
U.S. Pat. No. 4,797,300 (Jandacek et al.), issued Jan. 10, 1989 discloses the use of certain solid sucrose polyesters which have high oil binding capacity for liquid sucrose polyesters (SPE) and liquid triglycerides, when used at levels of about 10% to 25% in said oils. It is disclosed that because of their high oil binding capacity, these solid sucrose polyesters have outstanding utility as agents to control passive oil loss of liquid nondigestible sucrose polyesters, and they are also useful as non-caloric hardstocks to use with liquid digestible or nondigestible oils in the preparation of semi-solid fat products such as shortenings and margarines. The oil binding agents of the Jandacek et al. '300 patent are solid sucrose polyesters wherein the ester groups consist essentially of a mixture of short chain saturated fatty acid ester radicals (C.sub.2 -C.sub.10) and long chain saturated fatty acid radicals (C.sub.20 -C.sub.24) in a molar ratio of short chain to long chain of from about 3:5 to about 5:3, and wherein the degree of esterification is from about 7 to about 8. Jandacek et al. also disclose plastic shortening and other food compositions containing 10-25% of the solid SPE.
U.S. Pat. No. 4,005,195 (Jandacek), issued Jan. 25, 1977 describes a means of preventing the undesirable oil loss effect through the addition of oil-loss control agents. The oil-loss control agents include solid fatty acids (melting point 37.degree. C. or higher) and their triglyceride sources, and solid polyol fatty acid polyesters. Specifically C.sub.10 -C.sub.22 saturated fatty acid polyesters are said to be useful at levels of at least 10%, preferably at least 20%.
U.S. Pat. No. 3,158,490 (Baur et al.), issued Nov. 24, 1964 discloses sucrose (and other disaccharide) polyesters which are useful as additives at 0.001% to 0.5% level in triglyceride salad oils to prevent clouding in low-temperature storage of the oils. The degree of esterification is at least 3, i.e., no more than 5 of the 8 hydroxyl groups are unesterified. The ester groups are a combination of: (1) from 15-85% saturated C.sub.14-C.sub.22 fatty acids, and (2) the balance selected from saturated C.sub.2 -C.sub.12 or unsaturated C.sub.14 -C.sub.22 fatty acids. Arachidic (C.sub.20) and behenic (C.sub.22) acids are recited as specific examples of (1) and acetic (C.sub.2), caprylic (C.sub.8), and oleic (C.sub.18-1) acids are recited as specific examples of (2). At col. 2, lines 5-10, a sucrose ester having 2 oleic and 6 palmitic groups is disclosed, and it is stated that long chain saturated acids such as myristic, stearic, arachidic or behenic can be used in place of all or part of the palmitic.
U.S. Pat. No. 3,093,481 (Eckey et al.) issued Jun. 11, 1963 describes sucrose polyesters which are used at up to about 0.5% in shortenings to improve the physical aging characteristics of the shortening. The saccharides can be sucrose, lactose, maltose, etc. At least half of the hydroxyl groups are esterified with saturated C.sub.14-C.sub.22 acids. The remaining hydroxyl groups can be esterified with C.sub.2-C.sub.12 saturated acids and/or C.sub.14 -C.sub.22 unsaturated acids.
U.S. Pat. No. 4,880,657 (Guffey et al.), issued Nov. 14, 1989 discloses plastic shortening made with Intermediate Melting Fraction (IMF) polyol polyesters in combination with triglyceride hardstock and triglyceride oils. The solid fat content profile and penetration of the disclosed shortenings are adjusted to provide improved textural qualities to the shortening. Examples of IMF materials with the following fatty acid contents are disclosed: (1) 11.5% C.sub.16, 54.2% C.sub.18, 17.9% C.sub.18:1, 14.2% C.sub.18:2, 1% C.sub.18:3, 0.5% C.sub.20, and 0.3% C.sub.22 ; and (2) 9.6% C.sub.16, 50.6% C.sub.18, 21.6% C.sub.18:1, 15.7% C.sub.18:2, 1% C.sub.18:3, 0.5% C.sub.20 and 0.3% C.sub.22.
While these references disclose shortenings and oil which provide oil loss control, none of the references recognizes that oil loss control and good organoleptic properties can be achieved when the nondigestible portion of a reduced calorie shortening/oil has low solids levels (i.e. less than 10%).
It is, therefore, an object of the present invention to provide reduced calorie plastic shortenings which impart oil-loss leakage control, good textural properties, and also provide good organoleptic properties to foods prepared with them.
These and other objects of the invention will become evident from the disclosure herein.